German rocket guidance engineer, worked at Peenemuende on the V-2. He later worked in France at LRBA from 1947-1960 in the target acquisition avionics group. In the early 1950's he had done some work in Egypt, and in 1960 he joined with Jens-Goercke to established an avionics company in Bavaria. In the same year Saenger, Pilz and Goercke founded INTRA (International Rakete) for the purpose of providing German expertise to Nasser in the production of indigenous Egyptian ballistic missiles. Kleinwaechter was part of the effort, which eventually grew to 250 European engineers and 4,000 local employees. However Kleinwaechter and the other foreign workers were driven away by Israeli death threats and diplomatic pressure by the end of 1963. The rockets produced had not been tested enough to be reliable, and the Egyptians abandoned them and turned to the Soviet Union. Kleinwachter' s son, who had constantly argued against the morality of his father's decisions, converted the family firm to one dedicated not just to instrumentation but to solar energy engineering during the 1970's.

The Egyptian government exhibits mock-ups of missiles they are developing with assistance from German engineers. The El Qahir (conqueror) is 11 m long and was said to have a range of 600 km. The El Zafir (Victor) is 5.5 km long and had a range of 300 km. Later it is announced that a two-stage Al Ared (Pioneer) rocket is being developed that will have a range of 1000 km. A modification of this will be capable of launching satellites. Engineers involved in development of the rockets are said to be Wolfgang Pilz, Hans Goercke, and Hans Kleinwaechter. Eugen Saenger at the Stuttgart Propulsion Institute is also implicated. Saenger, who is working with his wife on steam-rocket boosted ramjet aircraft, denies this.